The goal of this proposal is to obtain a state-of-the-art ZetaView TWIN Laser Nanoparticle Tracking Analyzer (NTA) device at the University of Vermont (UVM). There is no comparable instrument on campus or at regional institutions, and it would meet the increasing demand and interest in a breadth of NTA research applications across campus. Further, as Vermont is an IDeA/EPSCRoR state, this device will be a further valuable resource to be shared through the IDeA/EPSCoR network. The requested device will enhance current research, and will be particularly essential for future cutting-edge nanoparticle research for the UVM Larner College of Medicine (LCOM) community. The instrument will be integrated into the LCOM Flow Cytometry and Cell Sorting Core Facility, ensuring access to researchers throughout the University. The rationale for a new instrument is to better enable a diverse and growing range of nanoparticle studies involving both biologic and non-biologic samples. The proposed TWIN laser NTA device, manufactured by Particle Metrix Inc., has been carefully vetted and chosen after extensive discussions with the manufacturer, as well as recent demos of competing NTA devices on the UVM campus. Seven investigators have been identified as Major Users for the purpose of this application, as they represent most of the projected demand for the requested instrument given their existing and proposed research applications and requirements. We have also identified a large and strong group of 18 minor users that will account for the remaining time on the proposed new system. Notably, between the major and minor users, a total of 21 users have NIH funding, accounting for 95% of the total accessible user time. The Major User and Minor User groups assembled for this proposal represent faculty and biomedical research interests in the UVM Larner College of Medicine from the Departments of Biochemistry, Medicine, Microbiology & Molecular Genetics, Molecular Physiology & Biophysics, Neuroscience, Pathology & Laboratory Medicine, and Pharmacology. Moreover, these faculty also represent the Vermont Cancer Center, the Cardiovascular Research Institute, the Vermont Lung Center, the Vermont Center for Immunology and Infectious Diseases, and the Cellular, Molecular, and Biomedical Sciences Graduate Program. Further strong interest and use will come from the UVM Colleges of Arts and Sciences, Engineering and Mathematical Sciences, and Nursing and Health Sciences. We further anticipate growing use from investigators at regional institutions. Thus, the addition of a ZetaView TWIN Laser NTA device will be a powerful tool to further the capacity for advanced high- quality investigations and ensure sustained and efficient use for the UVM biomedical research community for the future.